Eliminate RawObject::class_ field entirely.

runtime/vm/raw_object.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_RAW_OBJECT_H_
 #define VM_RAW_OBJECT_H_
 
 #include "platform/assert.h"
 #include "vm/globals.h"
 #include "vm/token.h"
@@ skipping 297 matching lines @@
   static bool IsNumberClassId(intptr_t index);
   static bool IsIntegerClassId(intptr_t index);
   static bool IsStringClassId(intptr_t index);
   static bool IsOneByteStringClassId(intptr_t index);
   static bool IsTwoByteStringClassId(intptr_t index);
   static bool IsExternalStringClassId(intptr_t index);
   static bool IsBuiltinListClassId(intptr_t index);
   static bool IsByteArrayClassId(intptr_t index);
 
  protected:
-  RawClass* class_;
   uword tags_;  // Various object tags (bits).
 
  private:
   class FreeBit : public BitField<bool, kFreeBit, 1> {};
 
   class MarkBit : public BitField<bool, kMarkBit, 1> {};
 
   class CanonicalObjectTag : public BitField<bool, kCanonicalBit, 1> {};
 
   class CreatedFromSnapshotTag : public BitField<bool, kFromSnapshotBit, 1> {};
@@ skipping 1172 matching lines @@
          kExternalUint64Array == kByteArray + 18 &&
          kExternalFloat32Array == kByteArray + 19 &&
          kExternalFloat64Array == kByteArray + 20 &&
          kClosure == kByteArray + 21);
   return (index >= kByteArray && index <= kClosure);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_